1. Field of the Invention
This invention relates to a speech communication system and method, and a robot apparatus and, in particular, is suitably applied to an entertainment robot, for example.
2. Description of the Related Art
Recently, various kinds of entertainment robots for general users have been produced. Some entertainment robots are provided with various external sensors such as charge coupled device (CCD) cameras and microphones, so as to recognize surrounding conditions based on outputs of the external sensors to autonomously behave based on the recognition results.
Further, some of those entertainment robots being proposed are provided with a face recognition function to extract a human face in a captured image and identify a specified person while tracking the face or a speech communication function to make conversation with a user, like humans usually do. (for example, refer to Japanese Patent Application Laid-Open 2003-062777 (second to third sections, FIG. 1)).
By the way, such an entertainment robot has to always confirm that a conversation partner is there while having conversation and to determine whether the robot is now having conversation with him/her.
In a dark place, the robot cannot recognize the conversation partner's face color and outline clearly, resulting in insufficient recognition of the face recognition function. In this case, the robot may determine that the partner is not there and stop the conversation although the partner is in front of the robot.
Further, in a situation where television or radio is turned on during conversation, since the speech communication function cannot distinguish between the television or radio and the conversation partner's voice, the robot may keep speaking even when the partner does not speak to the robot.
Therefore, if the robot can surely recognize the existence of a conversation partner under any environments, the robot can behave naturally like a human, so that the robot can have significantly improved entertainment property as an entertainment robot. This is strongly desired.